The present invention relates generally to electrical switches, and, more particularly, to illumination for switch members such as buttons.
It is well known in the automotive field that backlit control panels often use switch members with some form of illumination for nighttime visibility.
Often, the coloration of switch members is provided by a light filter media either connected to the light source or attached at the opening in the switch member. Also, switch members have been both molded in translucent, colored, plastic resin or simply coated in the desired color. However, it is cumbersome to manufacture and assemble light source covers or to paint or apply resin directly to the switch member opening. Also, colored plastic resins for the switch member is an added cost to manufacturing.
The disadvantages associated with these conventional switch member illumination techniques have made it apparent that a new technique for illuminating switch members is needed. The new technique should facilitate assembly of control panels and should not require colored plastic resins for the switch members. The present invention is directed to these ends.
It is, therefore, an object of the invention to provide an improved, reliable and less expensive assembly for illuminating switch members.
In one aspect of the invention, an illuminated switch member assembly is disclosed. The assembly includes an applique coupled to a faceplate and substantially parallel to a circuit board such that a first light channel is defined. The assembly also includes a switch member casing coupled to the faceplate such that a second light channel is defined by the walls of the casing. And, an actuator is connected to the circuit board through a contact mechanism and to the button member casing. The assembly further includes a light filter attached to the applique and disposed between the faceplate and the circuit board such that the light filter substantially divides the first light channel from the second light channel. Furthermore, a light source is disposed within the first light channel and emanates a light. Upon activation of the assembly, the light emanates from the light source and through the first light channel and the light filter. The light subsequently reflects off a surface on the actuator such that it travels through the second light channel to illuminate the switch member.
In another aspect of the invention, a process for directing light through a switch includes directing light from a light source through a circuit board and an applique coupled to a faceplate. The aforementioned elements define a first light channel. The process further includes filtering light through a light filter. After filtering the light, the light is reflected off a surface on an actuator connected to the circuit board into a casing for the switch member which defines a second light channel such that the light emanates from the switch member.
The present invention thus achieves an improved assembly for illuminating switch members. The present invention is advantageous in that it reduces part count for a control panel assembly and thus makes the assembly more reliable. Also, it simplifies the lighting of multiple colored switch members on the same control panel because the different colors are screened on the backlighting filters with the applique. Therefore, separate colored components mounted on the light source or the switch members themselves are unnecessary.
Additional advantages and features of the present invention will become apparent from the description that follows and may be realized by the instrumentalities and combinations particularly pointed out in the appended claims, taken in conjunction with the accompanying drawings.